This invention relates in general to equipment for sail boats and more particularly to a traveller device for positioning a sail.
In the prior art there are a variety of traveller devices used for positioning sails on different types of boats. These devices have relied upon the use of carrier bodies with flat surfaces which slide along the surfaces of a guide rail. In one such traveller device, the carrier body slide surfaces were on flat blades which projected one from each side of the carrier body.
These traveller devices which had sliding surface contact with the guide track were subject to certain disadvantages, such as excessive frictional resistance, easy blockage by sand and salt particles, and excessive vulnerability to rapid progressive failure. If a crack developed at one end of a slider blade, such crack would readily extend under load until the entire blade became separated from the carrier body.
The traveller device of the subject invention has a carrier body disposed for longitudinal movement along a guide track, and a base with at least one fitting, which base is connected to the carrier body for movement therewith to adjust a line that controls a sail, whereby the position of such sail is established by the location of the carrier body on the guide track. The invention provides an improvement which comprises a plurality of rollers borne by the carrier body on opposite sides thereof. These rollers are disposed in spaced-apart relation along the length of the carrier body and for rolling contact engagement with longitudinally extending surfaces of the guide track to accommodate the movement of the carrier body therealong.
In accordance with a preferred embodiment of the invention, the carrier body is made of a strong and somewhat elastic plastic material such as DELRIN, commonly designated as an elastomeric material, and the rollers are supported on axles that extend transversely through the carrier body and are supported thereby for rotation relative thereto.
It has been found that by using a series of independent rollers and an elastomeric carrier body, frictional resistance is reduced and there is no progressive failure problem as was encountered with slider blades. Particularly where the traveller device is used on small sailing catamarans, it is possible to have a low profile C-shaped cross section guide track, and to use correspondingly small diameter rollers, and yet have a much higher load safety factor than would be possible with slider blades of the same thickness as the roller diameter.
For a better understanding of the invention and its various advantages, reference should be had to the following detailed description and accompanying drawing which together exemplify a certain preferred embodiment of the invention.